1. Field of the Invention
This invention relates to a compound bow and more particularly to a mounting bracket for a compound bow in which the bracket is secured to the free end portion of a limb of the bow in a manner that reduces the stresses applied to the end of the limb by the connection of the bracket to the limb.
2. Description of the Prior Art
Compound bows, as well known in the art, include pulleys, wheels, or the like that are secured to the free ends of the bow limbs. The cable or arrow string is reeved about the pulleys, and with this arrangement a mechanical advantage is provided to increase the amount of potential energy stored in the limbs as the arrow string is drawn. Numerous arrangements are utilized to rotatably support the pulleys about an eccentric axis at the limb free end portions.
One method of rotatably mounting pulleys or the like on the free end portions of the bow limbs is disclosed in the following U.S. Pat. Nos.: 3,486,495; 3,958,551; 4,061,124 and 4,054,118 and includes the limb tips or free end portions having bifurcations in which a pin or axle is positioned. The eccentric pulley is rotatably mounted on the pin. It is believed, however, that a bow limb having a bifurcated tip for receiving and supporting an eccentrically mounted pulley has reduced structural strength in view of the bifurcation of the tip and subsequently has a failure rate exceeding that of compound bows with tips which are not bifurcated.
The limbs of the compound bow with a cable extending between the tips of the limbs is subjected to a constant torque. The torque is increased when the arrow string portion of the cable is pulled to the full draw position. Thus the bow limbs are under constant stress, and the resistance of the bow limbs to stress is substantially reduced by the bifurcated nature of the limb tips. This contributes to splitting or breaking of the bow limbs at the tips.
Another arrangement for mounting pulleys, wheels and like devices on the outer end portions of the limbs of a compound bow is disclosed in U.S. Pat. No. 4,064,862. Mounting brackets are fixedly secured to the outer end portions of the limbs by suitable fastening members that extend through aligned holes in the brackets and the end portions of the limbs. The fastening members extend through the aligned holes and engage the limbs. However, by engaging the fastening means to the limbs the outer end portions of the limbs are subjected to increased stress and are substantially weakened to resist the bending stresses applied to the limb end portions when the arrow string is drawn. This arrangement is known to result in failure of a limb by splitting or breaking at the point of contact of the fastening members with the limb end portions.
Therefore, there is need for an arrangement of securely mounting brackets on the outer end portions of compound bow limbs for rotatably supporting cable supporting devices that overcomes the disadvantages encountered with bifurcated limb end portions and threadedly engaging fastening members to the limb end portions. Thus by preventing a reduction in the resistance of the limb end portions to the torque applied thereto by bifurcating the limb end portions or by threadedly securing fastening members thereto in order to mount brackets on the limbs, failure of the bow limbs can be substantially prevented.